is there such a thing as a 8 1/4?

Hi Vortex. Just so you know since your post didn't really pertain to this original post it would have been better to start a new thread rather than hijack this one.

To answer your question the best I can I don't have a cross reference that lists the numbers that you listed so I can't tell by that. I just know them by sight. The 8-3/4 rear has no rear cover so if yours has no rear cover it's a 8-3/4, if it has a rear cover rule out the 8-3/4. That would mean it has to be a 8-1/4 or 7-1/4. The 8-1/4 has a rear cover that is oval shaped with 10 bolts. The 7-1/4 is pretty much round and a very light duty looking rearend. Hope this helps.

If you don't figure it out by this and have a way to post a pix do that. I can tell you by the look of it.